djpacro

On 25/04/2024 at 10:55 AM, facthunter said:

.....  I have tried to push "Unusual attitude recovery" at least for instructors. No one appears to be listening..  Nev

True, CASA's priorities for safety promotion are listed here Safety promotion sponsorship program | Civil Aviation Safety Authority (casa.gov.au) They seem to think that LOC-I is not an issue worth addressing.

On 25/04/2024 at 11:29 AM, Roundsounds said:

I have found as time goes on the majority of instructors are fearful of anything other than a wings level 1G stall. .... there’s the “pick up the wing with rudder” thing! Rudder is only used to prevent further yaw until you’re no longer stalled. 

Back when I started instructing (part-time) many years ago other instructors palmed off their advanced stall lessons in the Cessna 150 to me.

These days I do a lot of spin endorsements for flight instructor trainees for several flight schools. Too many cannot tell me the correct technique to recover from a stall in a turn.

(I also teach some to be spin and aerobatic flight instructors plus UPRT.)

7 hours ago, BrendAn said:

well i rang them again today. the jabiru at moorabbin with instructor is $490 per hour. i asked him twice to make sure. that is  a lot of money. the gazelle is off line.

Same money elsewhere will get a Piper Arrow dual. Seems like he doesn’t like to do much work.

2 hours ago, Blueadventures said:

How much is the Gazelle? As that may be the best for BrendAn as he will be flying the XAir to build hours.

Someone will have to ring Oasis again and ask.

1 hour ago, BrendAn said:

I asked about raaus but he may have not heard me . 

It does seem to be the right rate for a Piper PA-28.

35 minutes ago, BrendAn said:

I rang a flying school at Moorabbin and that's the price I got. It was oasis. Do you think he gave me a GA rate.

You spoke to them, not me. I guess that he simply answered the question that you asked.

1 hour ago, BrendAn said:

If you do raaus at Moorabbin you are paying around $420 p/h.

NOPE. At Moorabbin a Sling 2 is $364 to 368 dual.  Foxbat $328 dual. Also a Jabiru and Gazelle for training there.

4 hours ago, IanR said:

I now have ADSB out on my aircraft. Have just purchased a uavionix PING ADSB receiver to display ADSB traffic on OzRunways. Have not tried it yet but should give similar input to the Skyecho at a fraction of the price. 

Same here, new transponder with ADSB-out so fitted a Ping although I could’ve retained the SkyEcho. Of course, I use AvPlan.

it works well.

1 hour ago, aro said:

…. The service ceiling is the altitude at which the aircraft is unable to climb at a rate greater than 100 feet per minute (fpm). …… If you're familiar with Cessna 172 performance ….

Yes indeed. I lived in Wyoming USA for several years and flew a 172 (along with other types) from an airfield at 6500 ft elevation with summer temperatures up to 30 deg C. Illuminating.

On 15/03/2024 at 7:04 AM, Bosi72 said:

Great news djpacro, 

Any more information, eg. when and where?

Thanks

Rich will be hosted by Strike Aviation Training | Learn to Fly at Caboolture Airfield from 28th June until 2nd July. I will post the link to the webpage with details when I get it.

1 hour ago, tillmanr said:

The frying weather was the dominating part of the day. Aircraft wise it was reasonable but I am getting a bit blasé in my old age.

Me too, I left after Andrew’s display in the Extra - the heat affected his performance too. Even then it took ages to get out of the car park.

Quite a few people there, especially with that weather, so they would’ve been happy with their publicity. I would’ve flown in if the weather was better and I’d have offered red750 a seat.

I heard a rumour that Rich Stowell is visiting Australia soon for some seminars and flight training.

On 9/3/2024 at 2:20 PM, facthunter said:

Most spins not recovered from in this Plane type were fatals as the stabilised RoD is above 6,000 fpm in a spin.. You can see the high energy flat attitude results in the Photo. Deformation in the forward cockpit is extensive. I guess the amount of DHC-1 flying at that time was much less than in the 60s so the grapevine would be non existent..   Nev

Someone happened to catch it on video. 

On 06/03/2024 at 11:06 PM, LoonyBob said:

I'd love to see the report; I had my gossip (much later) from a couple of members of NSW DCA at the time...

Try this Collision with terrain involving DHC-1, 'Chipmunk' VH-UPD near Coffs Harbour, NSW on 29 June 2014 | ATSB

23 hours ago, LoonyBob said:

I understand that when John Thorp (of NSW Region DCA, not the designer bloke) was investigating the unrecovering Chipmunk mystery, he followed very much this routine (I don't know if he had a spin chute fitted, but he didn't deploy one); after spinning the first Chippie, he flew to base and reported that the aircraft was unrecoverable by normal means, and that the fleet was (would remain?) grounded until he had cleared each aircraft. He went on to spin every Chippie on the Australian register, and cleared each and every one with the new stick grip removed and the old one returned to service. Apparently, the conformal grip reduced the stick foward travel by a few mm, which was enough to make the difference.

I don't see any of that in the report? Nowhere do I see a mod to the stick grip however there is mention that harness may restrain positioning of the stick. 

22 hours ago, LoonyBob said:

The FAA flight test guide rests largely on RAeS/ARL and German data from pre-WW2; again, the FAA FTG is not a comprehensive first-principles study, but a guide for flight testing.

 

It is just this failure to distinguish between an incipient and full spin, that eroded the original Certification requirement to recover from a developed spin.

Not altogether, there's a wealth of information from NASA's GA spin research around the '70s which contributed significantly. 

I don't know what you mean about eroding "the original certification requirement"? 

I see some significant differences between CAR3 and FAR23 (the versions that applied to many aircraft around today). The latest FAR 23 is different again.

I'll have a look for that older spin material, thanks.

A recent USA AOPA article is relevant: https://aopa.org/training-and-safety/air-safety-institute/accident-analysis/flight-training-accident-report

Quote

Additionally, there have been substantial changes in stall recovery training at the airline transport pilot (ATP) level, the highest level of civilian pilot certification. These changes, which took effect in 2012, emphasize the importance of reducing the angle of attack (AOA) as the first and primary step in stall recovery. Although this emphasis on AOA reduction instead of powering out of the stall has been most pronounced at the ATP level, the attention on proper stall recovery has benefitted the entire industry. .....

The aviation industry has done an excellent job of messaging the risk of a stall/spin accident when overshooting base to final. The industry should make similar efforts to message the risk of stall during takeoff, climbout, and go-around, and emphasize the importance of energy awareness in this critical phase of flight. ....

Instructors should review the FAA’s stall recovery template (Figure 5-10 of the Airplane Flying Handbook) to ensure that they are teaching stall recovery to current guidelines.4 Specialized training in upset prevention and recovery training (UPRT) is also encouraged.

CASA issued AC61-16, Spin avoidance and stall recovery training , about 4 years ago which is consistent with Figure 5-10 of the Airplane Flying Handbook.

However, the CASA Flight Instructor Manual has not been revised per ATSB Investigation AO-2017-096 of 22/5/2019.

In the USA:

Quote

Instructional aviation has a lower accident rate than GA overall and has seen safety improve at a faster pace.

Not so per the Australian Transport Safety Bureau AR-2020-047 Aviation Occurrence Statistics (rates update) 2010 to 2019 (the latest data):

Quote

Further, the number of GA operational-related accidents and serious incidents, per year, increased over the period. Instructional flying was the main contributor to this operational-related increase."

To repeat: in the USA flight instruction safety has improved whereas in Australia it has worsened. 

From Issue 107 of SportPilot Magazine we have this:

Fine as far as it goes however, I didn't see any guidance on the use of rudder. It states to "level the wings" without explaining the technique.

Better to stick with the FAA's Figure 5-10 and associated text of the Airplane Flying Handbook.

If one believes CASA's Flight Instructor Manual one would believe that the recovery method from an incipient spin is different from a fully developed spin. Identify when one is no longer in an incipient spin and suddenly the recovery action is different. See my extract from Cessna's Spin Booklet above, repeated here:

"During this incipient phase, spin recoveries in those airplanes approved for intentional spins are usually rapid, and, in some airplanes, may occur merely by relaxing the pro-spin rudder and elevator deflections. However, positive spin recovery control inputs should be used regardless of the phase of the spin during which recovery is initiated."

The test pilots and engineers who write the bits ablout spinning in flight manuals follow FAA AC 23-8C FLIGHT TEST GUIDE FOR CERTIFICATION OF PART 23 AIRPLANES which defines the spin:

Quote

A spin is a sustained autorotation at angles-of-attack above stall. The rotary motions of the spin may have oscillations in pitch, roll, and yaw superimposed upon them. The fully developed spin is attained when the trajectory has become vertical and the spin characteristics are approximately repeatable from turn to turn. Some airplanes can autorotate for several turns, repeating the body motions at some interval, and never stabilize. Most airplanes will not attain a fully developed spin in one turn.

No mention of the word "incipient" at all in that document.

When the word "spin" or "spinning" is used in the AFM or POH then it simply means "a sustained autorotation" and use the method in that AFM/POH for spin recovery.

That is especially important for types not approved for intentional spinning as they have only been tested for recoveries from a spin of up to one turn.

Picking up that Cessna statement again: "During this incipient phase, spin recoveries in those airplanes approved for intentional spins are usually rapid, and, in some airplanes, may occur merely by relaxing the pro-spin rudder and elevator deflections." "may occur" ... well, of course, the spin behaviour is changing all throughout the incipient spin phase so don't expect that to work at the instant just prior to the established fully developed spin.

However, it is a good technique for aerobatic pilots, in a type approved for intentional spins, at the onset of autorotation to centralise the controls and close the throttle.

I noticed this site promoting CASA's Flight Instructor Manual. One would expect CASA’s Flight Instructor Manual to be a reputable source of correct information on spinning however ATSB Investigation AO-2017-096 of 22/5/2019 found otherwise.

Quote

Incorrect guidance

While the ATSB assessed that the instructor’s incipient spin recovery knowledge was consistent with established guidelines and did not contribute to the accident, the investigation identified incorrect incipient spin recovery guidance provided by CASA.

The CASA publication Flight Instructor Manual, provides the following guidance for incipient spin recovery:

---

RECOVERY FROM THE INCIPIENT STAGE

As soon as the aeroplane has stalled and commenced to yaw take the appropriate recovery action. Increase power, apply sufficient rudder to prevent further yaw and ease the control column forward sufficiently to un-stall the aeroplane. Point out that if power is to materially assist recovery action it must be applied before the nose of the aeroplane has pitched too far below the horizon otherwise its use will only increase the loss of height.

---

 

Increasing engine power prior to an application of sufficient rudder to prevent further yaw and applying sufficient nose-down elevator un-stall the wings as described is inconsistent with established guidelines and manufacturer guidance.

 

The United States Federal Aviation Administration publication Airplane Flying Handbook, Chapter 5: Maintaining Aircraft Control: Upset Prevention and Recovery Training provides the following guidance, consistent with established guidelines, regarding spin recovery:

To accomplish spin recovery, always follow the manufacturer’s recommended procedures. In the absence of the manufacturer’s recommended spin recovery procedures and techniques, use the spin recovery procedures in the spin recovery template. If the flaps and/or retractable landing gear are extended prior to the spin, they should be retracted as soon as practicable after spin entry.

 

Spin recovery template:

1. Reduce the Power (Throttle) to Idle
2. Position the Ailerons to Neutral
3. Apply Full Opposite Rudder against the Rotation
4. Apply Positive, Brisk, and Straight Forward Elevator (Forward of Neutral)
5. Neutralize the Rudder After Spin Rotation Stops
6. Apply Back Elevator Pressure to Return to Level Flight.

 

The handbook also provides further guidance regarding power use during spin recovery:

Reduce the Power (Throttle) to Idle. Power aggravates spin characteristics. It can result in a flatter spin attitude and usually increases the rate of rotation.

CASA advised the ATSB that this matter will be referred to Safety Education for review and correction as required.

When that ATSB report was issued “CASA has advised the ATSB that they have taken the following safety action …..” i.e. they reviewed the above text in the Flight Instructor Manual but took no action so they must believe it to be correct.

One of the gems is Cessna's booklet which was published back in the '70s to counter misinformation about spinning. About time that it was promoted again.

https://mikeklochcfi.files.wordpress.com/2018/03/cessna-spin-manual.pdf

It has much general information (obviously a lot of information speciific to the Cessna so be careful about generalising) too with information such as:

"For the purpose of this discussion, we will divide the spin into three distinct phases. ..... Here, in the entry phase, recovery from or prevention of the spin is as simple as normal stall recovery since, in fact, at this point that's all we are really faced with. .... 

During this incipient phase, spin recoveries in those airplanes approved for intentional spins are usually rapid, and, in some airplanes, may occur merely by relaxing the pro-spin rudder and elevator deflec- tions. However, positive spin recovery control inputs should be used regardless of the phase of the spin during which recovery is initiated. ....

Due to the attitude of the airplane in a spin the total motion is made up of roiling and usually pitching motions as well as the predominate yawing motions. Movement of the airplane flight controls affects the rate of motion about one of the axes. Because of the strong gyroscopic influences in the spin, improper aerodynamic control inputs can have an adverse affect on the spin motion. ....

Some of the additional factors which have (or may have) an effect on spin behavior and spin recovery characteristics are aircraft loading (distribution, center of gravity and weight), altitude, power, and rigging.

Distribution of the weight of the airplane can have a significant effect on spin behavior. The addition of weight at any distance from the center of gravity of the airplane will increase its moment of inertia about two axes. This increased inertia independent of the center of gravity location or weight will tend to promote a less steep spin attitude and more sluggish recoveries.

Forward location of the c. g. will usually make it more diffi- cult to obtain a pure spin due to the reduced elevator effectiveness."

I mentioned that effect of moment of inertia in another thread. Pilots get to determine weight and CG but, as Cessna stated above, the increased moment of inertia is independent of weight and CG. eg fuel in outboard wing tanks vs inboard wing tanks. However, we usually deal with small changes in weight and CG associated with a large change in moment of inertia. Pilots have been be caught out with small ballast weights added near the tail to adjust CG with no consideration given to the moment arm squared and the big increase in moment of inertia.

What some pilots (or the accident investigators) have observed to be the result of a small CG change was actually caused by a change in moment of inertia.

NB: the USA FAA supported this booklet with their bulletin to all flight instructors back then. 

A spin resistance standard was added to the FAR 23 airworthiness design and testing requirements in 1991. The Columbia 300 was certified to this standard in 1998. It carries clear warnings in the POH "Do not attempt to spin the airplane under any circumstances ..... During the flight test phase of the airplane's certification, spins were not performed. It is not known if the airplane will recover from a spin."

The Cirrus was certified with an Equivalent Level of Safety by having the CAPS. Perhaps considered to have a spin resistant wing design as they followed some guidance from NASA with this. Anyway, the Cirrus spin certification and some spin testing done for EASA is a longer story for perhaps another day as it is slightly off topic.

2 minutes ago, BrendAn said:

I was told that Steve Cohen designed thrusters to be spin resistant. Does not mean it's true though.

Spin resistant does not mean that it won't spin nor that, if it does, it will recover.

A spin about 2 minutes into this video. Just because it recovered from this spin does not mean that it will recover from other spin modes.

J 

19 hours ago, djpacro said:

To go a bit deeper into the subject for much of the underpinning knowledge required by CASA for a spin endorsement I suggest starting with NASA TN D-6575 SUMMARY OF SPIN TECHNOLOGY AS RELATED TO LIGHT I GENERAL-AVIATION AIRPLANES by James Bowman (I worked with Jim for a while). It is engineering stuff however fairly light reading.

 

"The way in which the mass of an airplane is distributed between the wing and fuselage is the most important single factor in spinning because it determines the way in which the airplane, while spinning, responds to control movements, especially to elevators and ailerons. An airplane rotating in a spin can be considered to be a large gyroscope. Since there are mass and angular rotation about all three axes, inertia moments are produced about all three axes."

Fig 3 shows the balance of pitching moments in a spin which basically determines the angle of attack in the fully developed spin. The nose down aerodynamic moments vs the nose up moments from inertia.

Worth repeating NASA's statement: "The way in which the mass of an airplane is distributed between the wing and fuselage is the most important single factor in spinning ..." NASA is not referring to CG there but to the moments of inertia.

"In order for the airplane to recover from the spin, the equilibrium must be broken, and this is normally accomplished by changing the aerodynamic moment by moving a control or combination of controls that can cause the greatest antispin moment. .......

The loading of the airplane dictates the control movements required for recovery. ..... Deflection of the rudder to oppose the spinning rotation directly is always recommended, but in many cases, it is not adequate to provide recovery. For the wing-heavy loadings, down elevator is the primary recovery control."

"Three factors are of almost overriding importance with regard to spin and recovery characteristics: (a) The relative distribution of the mass of the airplane between the wing and fuselage, which is commonly expressed in terms of the inertia yawing-moment parameter, a nondimensional factor relating the rolling and pitching moments of inertia (b) The tail configuration, which must provide damping for the spinning rotation and the rudder power for recovery and which is commonly evaluated in terms of an empirically determined tail-damping power factor (c) The density of the airplane relative to the density of the air, which is commonly expressed in terms of the relative-density factor"

We don't need to concern ourselves with effects of air density so just moments of inertia and tail design.

Some aircraft types have weak nose down pitching moments so the nose up inertia moments drive them towards a much higher angle of attack in the spin. NASA has shown this for the Grumman AA-1 

CASA's Part 61 MOS requires this as essential knowledge for all pilots:

"Differentiate between a spin and a spiral dive in a light aeroplane and describe the standard recovery technique for each manoeuvre."

Yet I regularly encounter pilots and students who do not know the "standard" recovery technique for a spin.

Worse, I regularly encounter flight instructors and trainee flight instructors who also do not know the correct recovery technique - either that "standard" one or, more importantly, the one described in the flight manual of the type they fly. They are required to have a spin flight activity endorsement so a greater underpinning knowledge and competency. Recently, a flight examiner failed two flight instructor candidates on the ground component of their test because they described dangerously incorrect spin recovery technique in their theory briefing.

CASA helped recently with their AC 61-16 Spin avoidance and stall recovery training

The FAA's Airplane Flying Handbook, Chapter 5: Maintaining Aircraft Control: Upset Prevention and Recovery Training has excellent information.

To go a bit deeper into the subject for much of the underpinning knowledge required by CASA for a spin endorsement I suggest starting with NASA TN D-6575 SUMMARY OF SPIN TECHNOLOGY AS RELATED TO LIGHT I GENERAL-AVIATION AIRPLANES by James Bowman (I worked with Jim for a while). It is engineering stuff however fairly light reading.

20 hours ago, F10 said:

Yes, in a fully developed spin, moments of inertia in roll pitch and yaw, may have built up to an extent ..... I should have mentioned there are moment of inertia differences in an incipient and fully developed spin.

Not really, moment of inertia is simply a property of mass and geometry of the aeroplane.

Quote

Don't know the Decathlon, but I find it interesting the spin flattens. Should only occur with power on.

My statement was: "I can get the usually docile Decathlon to snap into a spin with little warning and be in an established, flattening spin extremely quickly ..." yes, with power and aileron - typical scenario for an unintentional spin. I wasn't referring to the normal practice spins with power off and neutral aileron.

There is more that I'd like to discuss so I will commence another thread for this.